The veteran actor has a vested reason: For his portrayal of the so-called "Trinity Killer" in Season 4 of the Showtime drama, he earned several awards including an Emmy and a Golden Globe. As he now watches
Michael C. Hall as the title murderer in the eighth and last round of the Sunday series, he admits to having pangs about the show' s imminent end.

"I went to a premiere party for the final season and saw all those guys for the first time in a couple of years," the pleasant Lithgow tells
Zap2it, "and it was very sentimental. I really felt very much a part of that group, even though I was only there for one-eighth of the time [of the series' overall history]. I felt very connected, probably because Trinity struck such a chord."

He most certainly did, leaving a lasting, haunting calling card: his apparent killing of Dexter's wife Rita (
Julie Benz), found dead in a bathtub as the couple's then-infant son Harrison sat in a pool of blood nearby.

"When people think of the entire eight years, they tend to think of Trinity as the worst of the villains, the most terrifying," Lithgow says. "He left his little signature there."

Set to voice the White Rabbit in the upcoming ABC spinoff
"Once Upon a Time in Wonderland," Lithgow owns three more Emmys for the sitcom
"3rd Rock From the Sun," plus one for the
Steven Spielberg-produced anthology
"Amazing Stories." While his busy schedule often involves traveling to perform his one-man stage show
"Stories by Heart," Lithgow always has managed to keep an eye on "Dexter."

"I was delighted to see
Colin Hanks come on," he says, "and now,
Charlotte Rampling. They've done an amazing job sustaining the show for all these years. And they're fabulous people there."